JP2015152037A - Power transmission device of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate unbalanced state of surface pressures of one-way clutch caused by twisting of an output shaft of a crank type stepless transmission mechanism.SOLUTION: Since a free end side of an output shaft 13 is twisted and deformed in respect to a restricted end side provided with a drive force output part 13b, there occurs a possibility at one-way clutch 36 that a surface pressure of a roller 41 installed between an inner circumferential surface 42a of an oscillating link 42 and an outer circumferential surface 13a of the output shaft 13 becomes non-uniform in an axial direction and the roller 41 is inclined to prohibit a smooth engagement of the one-way clutch 36. However, the oscillating link 42 is constituted in such a way that a side near the drive force output part 13b of one end side and the other end side holding its axial center (a side with lower surface pressure and the free end side) is made thin to have a low rigidity and a side far from the drive force output part 13b (a low surface pressure side and a free end side) is made thick to have a high rigidity, thereby the surface pressure of the roller 41 is made uniform in an axial direction to enable a smooth engagement of the one-way clutch 36 to be carried out.

Description

  The present invention relates to a vehicle power transmission device in which an input shaft and an output shaft are connected by a crank type continuously variable transmission mechanism.

  Crank type that converts the rotation of the input shaft connected to the engine into a reciprocating motion of the plurality of connecting rods having mutually different phases, and converts the reciprocating motion of the plurality of connecting rods into a rotating motion of the output shaft by a plurality of one-way clutches. This continuously variable transmission mechanism is known from Patent Document 1 below.

JP-T-2005-502543

  FIG. 12 schematically shows the periphery of the output shaft of such a crank type continuously variable transmission mechanism. The crankshaft continuously swings around the output shaft 02 supported by bearings 01 and 01 via a plurality of one-way clutches 03. The links 04 are supported, and when the swinging links 04 are swung in one direction by the connecting rods 05, the one-way clutch 03 is engaged and the driving force is transmitted to the output shaft 02. Since the driving force is output to the differential gear 06 from the spline 02a provided at one end (constraint end) of the output shaft 02, the output shaft is driven by torque input from the plurality of one-way clutches 03 supported on the outer periphery of the output shaft 02. The other end (free end) of 02 is twisted with respect to the one end (restraint end).

  In each one-way clutch 02, when the swing link 04 swings in one direction and the inner peripheral surface of the swing link 04 and the outer peripheral surface of the output shaft 02 rotate relative to each other, the roller 07 of the one-way clutch 02 rotates the swing link. Since the torque is transmitted between the inner peripheral surface of 04 and the outer peripheral surface of the output shaft 02, when the output shaft 02 is twisted by the torque input from the one-way clutch 02, the swing link 04 is increased by the twist angle. The relative rotational angle between the inner peripheral surface of the roller and the outer peripheral surface of the output shaft 02 decreases, and the biting of the roller 07 becomes locally shallow, and the surface pressure of the roller 07 cannot be made uniform over the entire axial direction. There's a problem.

  Specifically, when the right end side of the roller 07 close to the constraining end of the output shaft 02 is used as a reference, the twist angle increases toward the left end side of the roller 07 close to the free end of the output shaft 02. On the right end side, the relative rotation angle of the swing link 04 and the output shaft 02 is increased, and the roller 07 is deeply engaged between the inner peripheral surface and the outer peripheral surface to increase the surface pressure (FIG. 13A). Reference), the relative rotation of the swing link 04 and the output shaft 02 is small on the free end side (left end side) of the roller 07, and the roller 07 is shallowly engaged between the inner peripheral surface and the outer peripheral surface to reduce the surface pressure. (See FIG. 13 (B)), there is a possibility that the roller 07 is inclined due to the imbalance of the surface pressure and the smooth engagement of the one-way clutch 03 is hindered.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to eliminate imbalance in the roller surface pressure of a one-way clutch due to twisting of an output shaft of a crank type continuously variable transmission mechanism.

  In order to achieve the above object, according to the invention described in claim 1, a transmission unit that shifts the rotation of the input shaft connected to the drive source and transmits the rotation to the output shaft is provided. An eccentric member that rotates eccentrically with the input shaft, a swing link that is swingably supported by the output shaft, and the output shaft and the swing link are disposed between the output shaft and the swing link, and the swing link swings in one direction. A vehicle power transmission device comprising: a one-way clutch that engages when moved and disengages when swung in the other direction; and a connecting rod that connects the eccentric member and the swing link, The one-way clutch includes a plurality of rollers disposed between an inner peripheral surface of the swing link and an outer peripheral surface of the output shaft, and the output shaft includes a driving force output unit that outputs a driving force to driving wheels, The swing link is Of the one end side and the other end side sandwiching the center in the axial direction, the side close to the driving force output part is thin in the radial direction or axial direction, and the side far from the driving force output part is thick in the radial direction or axial direction. A vehicular power transmission device is proposed.

  According to the invention described in claim 2, in addition to the configuration of claim 1, the swing link is close to the driving force output portion among one end side and the other end side sandwiching the axial center. A vehicle power transmission device is proposed in which the side is thin in the radial direction and the side far from the driving force output portion is thick in the radial direction.

  The spline 13b of the embodiment corresponds to the driving force output unit of the present invention, the eccentric disk 19 of the embodiment corresponds to the eccentric member of the present invention, and the engine E of the embodiment serves as the driving source of the present invention. Correspond.

  According to the first aspect, when the eccentric member rotates eccentrically with the input shaft, the connecting rod having one end connected to the eccentric member reciprocates, and the swing link to which the other end of the connecting rod is connected reciprocates. Swing. The one-way clutch includes a plurality of rollers disposed between the inner peripheral surface of the swing link and the outer peripheral surface of the output shaft, and the one-way clutch is engaged when the swing link swings in one direction. When the one-way clutch disengages when it swings in the other direction, the rotation of the input shaft is shifted and transmitted to the output shaft.

  Since the output shaft includes a driving force output unit that outputs driving force to the driving wheels, the torque that is input from the one-way clutch on the free end side away from the driving force output unit relative to the restraining end side on which the driving force output unit is provided As a result of the torsional deformation, the surface pressure of the roller arranged between the inner peripheral surface of the swing link and the outer peripheral surface of the output shaft becomes non-uniform in the axial direction, and the roller tilts and the one-way clutch is smoothly engaged. May be hindered.

  However, the oscillating link is rigid with the side close to the driving force output part (the side with high surface pressure, the constraining end side) of one end and the other end sandwiching the center in the axial direction being thin in the radial direction or the axial direction. The surface pressure of the roller is made uniform in the axial direction by increasing the rigidity by making the side far from the driving force output part (the low surface pressure side, the free end side) thicker in the radial direction or the axial direction. The one-way clutch can be smoothly engaged.

  According to the second aspect of the present invention, the rocking link has one end side and the other end side sandwiching the center in the axial direction, the side close to the driving force output unit is thin in the radial direction, and is far from the driving force output unit. Since the side is made thicker in the radial direction, when the swing link is manufactured by forging or casting using a mold, it is easy to remove the die by matching the thick part with the mating surface of the mold Productivity is improved.

1 is an overall perspective view of a vehicle power transmission device. FIG. (First embodiment) The partially broken perspective view of the principal part of the power transmission device for vehicles. (First embodiment) FIG. 3 is a sectional view taken along line 3-3 in FIG. 1. (First embodiment) FIG. 4 is an enlarged view of part 4 of FIG. 3. (First embodiment) FIG. 5 is a sectional view taken along line 5-5 of FIG. (First embodiment) The figure which shows the shape of an eccentric disk. (First embodiment) The figure which shows the relationship between the eccentric amount of an eccentric disk, and a gear ratio. (First embodiment) The figure which shows the state of the eccentric disk in OD transmission ratio and GN transmission ratio. (First embodiment) The perspective view of a rocking | fluctuation link. (First embodiment) FIG. 10 is a sectional view taken along line 10-10 in FIG. 9; (First embodiment) The figure corresponding to FIG. (Second and third embodiments) Explanatory drawing of the twist of the output shaft by the torque from a one-way clutch. FIG. 13 is a cross-sectional view taken along line 13A-13A and 13B-13B in FIG.

First embodiment

  Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.

  As shown in FIGS. 1 to 5, an input shaft 12 and an output shaft 13 are supported in parallel with each other on a pair of side walls 11 a and 11 b of a transmission case 11 of a continuously variable transmission T for an automobile. The rotation of the connected input shaft 12 is transmitted to the drive wheels via the six transmission units 14, the output shaft 13 and the differential gear D. A spline 13b (see FIG. 1) connected to the differential gear D is formed at the right end of the output shaft 13, and the right end on which the spline 13b is formed is defined as a constraining end of the output shaft 13, and the left end on the opposite side. Is defined as the free end.

  A variable speed shaft 15 sharing an axis L with the input shaft 12 is fitted into the hollow formed input shaft 12 via seven needle bearings 16 so as to be relatively rotatable. Since the structure of the six transmission units 14 is substantially the same, the structure will be described below with one transmission unit 14 as a representative.

  The transmission unit 14 includes a pinion 17 provided on the outer peripheral surface of the transmission shaft 15, and the pinion 17 is exposed from an opening 12 a formed in the input shaft 12. A disc-shaped eccentric cam 18 divided into two in the direction of the axis L is splined to the outer periphery of the input shaft 12 so as to sandwich the pinion 17. The center O1 of the eccentric cam 18 is eccentric with respect to the axis L of the input shaft 12 by a distance d. Further, the six eccentric cams 18 of the six transmission units 14 are offset in phase by 60 ° from each other.

  On the outer peripheral surface of the eccentric cam 18, a pair of eccentric recesses 19 a and 19 a formed on both end surfaces in the axis L direction of the disc-shaped eccentric disk 19 are rotatably supported via a pair of needle bearings 20 and 20. . The center O1 of the eccentric recesses 19a, 19a (that is, the center O1 of the eccentric cam 18) is shifted from the center O2 of the eccentric disk 19 by a distance d. That is, the distance d between the axis L of the input shaft 12 and the center O1 of the eccentric cam 18 and the distance d between the center O1 of the eccentric cam 18 and the center O2 of the eccentric disk 19 are the same.

  A pair of crescent-shaped guide portions 18a and 18a are provided on the split surface of the eccentric cam 18 divided into two in the direction of the axis L so as to be coaxial with the center O1 of the eccentric cam 18. The tooth tips of the ring gear 19b formed so as to communicate between the bottoms of the recesses 19a and 19a slidably contact the outer peripheral surfaces of the guide portions 18a and 18a of the eccentric cam 18. Then, the pinion 17 of the transmission shaft 15 meshes with the ring gear 19b of the eccentric disk 19 through the opening 12a of the input shaft 12.

  The right end side of the input shaft 12 is directly supported by the right side wall 11 a of the mission case 11 via a ball bearing 21. A cylindrical portion 18b (see FIG. 4) provided integrally with one eccentric cam 18 located on the left end side of the input shaft 12 is supported on the left side wall 11b of the mission case 11 via a ball bearing 22. The left end side of the input shaft 12 splined to the inner periphery of the eccentric cam 18 is indirectly supported by the left side wall 11 b of the mission case 11.

  The speed change actuator 23 that changes the speed ratio of the continuously variable transmission T by rotating the speed change shaft 15 relative to the input shaft 12 is supported by the transmission case 11 so that the motor shaft 24a is coaxial with the axis L. A motor 24 and a planetary gear mechanism 25 connected to the electric motor 24 are provided. The planetary gear mechanism 25 includes a carrier 27 that is rotatably supported by an electric motor 24 via a needle bearing 26, a sun gear 28 that is fixed to the motor shaft 24a, and a plurality of two stations that are rotatably supported by the carrier 27. A pinion 29 and a first ring gear 30 provided on a first connection member 43 splined to the shaft end of the hollow input shaft 12 (strictly speaking, the cylindrical portion 18b of the one eccentric cam 18) And a second ring gear 31 provided on a second connection member 44 splined to the shaft end of the transmission shaft 15. Each double pinion 29 includes a first pinion 29a having a large diameter and a second pinion 29b having a small diameter. The first pinion 29a meshes with the sun gear 28 and the first ring gear 30, and the second pinion 29b has a second ring gear. Mesh with 31.

  On the outer periphery of the eccentric disk 19, an annular portion 33 a on one end side of the connecting rod 33 is supported via a roller bearing 32 so as to be relatively rotatable.

  The output shaft 13 is supported by a pair of ball bearings 34, 35 on a pair of side walls 11 a, 11 b of the mission case 11, and a swing link 42 is supported on the outer periphery via a one-way clutch 36. The tip of is connected to the tip of the rod portion 33 b of the connecting rod 33 via a pin 37. The one-way clutch 36 is disposed in a wedge-shaped space formed between the inner peripheral surface 42a of the swing link 42 constituting the outer member and the outer peripheral surface 13a of the output shaft 13 constituting the inner member. A plurality of rollers 41 urged by springs 40 are provided.

  As shown in FIGS. 6 and 8, since the center O1 of the eccentric recesses 19a and 19a (that is, the center O1 of the eccentric cam 18) is shifted from the center O2 of the eccentric disk 19 by a distance d, the outer circumference of the eccentric disk 19 And the inner periphery of the eccentric recesses 19a, 19a are non-uniform in the circumferential direction, and crescent-shaped thinning recesses 19c, 19c are formed at portions where the interval is large.

  Next, the operation of one transmission unit 14 of the continuously variable transmission T will be described.

  As is clear from FIGS. 5 and 7A to 7D, when the input shaft 12 is rotated by the engine E when the center O2 of the eccentric disk 19 is eccentric with respect to the axis L of the input shaft 12. As the annular portion 33a of the connecting rod 33 rotates eccentrically around the axis L, the rod portion 33b of the connecting rod 33 reciprocates.

  As a result, when the connecting rod 33 is pulled back and forth in the process of reciprocating movement, the rollers 41 urged by the springs 40 are moved between the inner peripheral surface 42 a of the swing link 42 and the outer peripheral surface 13 a of the output shaft 13. , The swing link 42 and the output shaft 13 are coupled via the rollers 41... So that the one-way clutch 36 is engaged and the movement of the connecting rod 33 is transmitted to the output shaft 13. . On the other hand, when the connecting rod 33 is reciprocated and pushed to the right side in the figure, the rollers 41 compress the springs 40 while being wedged between the inner peripheral surface 42a of the swing link 42 and the outer peripheral surface 13a of the output shaft 13. When the swing link 42 and the output shaft 13 slip each other, the one-way clutch 36 is disengaged and the movement of the connecting rod 33 is not transmitted to the output shaft 13.

  Thus, since the rotation of the input shaft 12 is transmitted to the output shaft 13 for a predetermined time while the input shaft 12 rotates once, the output shaft 13 rotates intermittently when the input shaft 12 rotates continuously. Since the eccentric disks 19 of the six transmission units 14 are out of phase with each other by 60 °, the six transmission units 14 alternately transmit the rotation of the input shaft 12 to the output shaft 13. Thus, the output shaft 13 rotates continuously.

  In the process of transmitting the driving force from the input shaft 12 to the output shaft 13, the larger the eccentric amount ε of the eccentric disk 19, the greater the reciprocating stroke of the connecting rod 33 and the one rotation angle of the output shaft 13 increases. The transmission ratio of the continuously variable transmission T is reduced. Conversely, the smaller the eccentric amount ε of the eccentric disk 19, the smaller the reciprocating stroke of the connecting rod 33, the smaller the rotation angle of the output shaft 13, and the higher the gear ratio of the continuously variable transmission T. When the eccentric amount ε of the eccentric disk 19 becomes zero, the connecting rod 33 stops moving even when the input shaft 12 rotates, so the output shaft 13 does not rotate, and the gear ratio of the continuously variable transmission T is maximized ( Infinite) geared neutral GN.

  When the transmission shaft 15 does not rotate relative to the input shaft 12, that is, when the input shaft 12 and the transmission shaft 15 rotate at the same speed, the transmission ratio of the continuously variable transmission T is maintained constant. In order to rotate the input shaft 12 and the transmission shaft 15 at the same speed, the electric motor 24 may be rotationally driven at the same speed as the input shaft 12. The reason is that the first ring gear 30 of the planetary gear mechanism 25 is connected to the input shaft 12 and rotates at the same speed as the input shaft 12. When the electric motor 24 is driven at the same speed, the sun gear 28 and the first ring gear 30 are driven. Rotate at the same speed, the planetary gear mechanism 25 is locked and rotates as a whole. As a result, the input shaft 12 and the transmission shaft 15 connected to the first ring gear 30 and the second ring gear 31 that rotate integrally are integrated and rotate at the same speed without relative rotation.

  When the rotational speed of the electric motor 24 is increased or decreased with respect to the rotational speed of the input shaft 12, the first ring gear 30 coupled to the input shaft 12 and the sun gear 28 connected to the electric motor 24 rotate relative to each other. The carrier 27 rotates relative to the first ring gear 30. At this time, the gear ratio of the first ring gear 30 and the first pinion 29a meshing with each other is slightly different from the gear ratio of the second ring gear 31 and the second pinion 29b meshing with each other. And the transmission shaft 15 connected to the second ring gear 31 rotate relative to each other.

  When the transmission shaft 15 rotates relative to the input shaft 12 in this manner, the eccentric recesses 19 a and 19 a of the eccentric disk 19 in which the ring gear 19 b is engaged with the pinion 17 of each transmission unit 14 are integrated with the input shaft 12. The cam 18 rotates while being guided by the guide portions 18a, 18a, and the eccentric amount ε of the center O2 of the eccentric disk 19 with respect to the axis L of the input shaft 12 changes.

  FIG. 7A shows a state where the gear ratio is minimum (overdrive: OD). At this time, the eccentric amount ε of the center O2 of the eccentric disk 19 with respect to the axis L of the input shaft 12 is the axis L of the input shaft 12. To a center O1 of the eccentric cam 18 and a maximum value equal to 2d, which is the sum of the distance d from the center O1 of the eccentric cam 18 to the center O2 of the eccentric disk 19. As shown in FIGS. 7B and 7C, when the transmission shaft 15 rotates relative to the input shaft 12, the eccentric disk 19 rotates relative to the eccentric cam 18 integral with the input shaft 12. Furthermore, the eccentric amount ε of the center O2 of the eccentric disk 19 with respect to the axis L of the input shaft 12 is gradually decreased from the maximum value 2d, and the transmission ratio is increased. When the transmission shaft 15 further rotates relative to the input shaft 12, the eccentric disk 19 further rotates relative to the eccentric cam 18 integral with the input shaft 12, and finally, as shown in FIG. The center O2 of the eccentric disk 19 overlaps the axis L of the input shaft 12, the eccentricity ε becomes zero, and the transmission ratio is maximized (infinite) (geared neutral: GN) to transmit power to the output shaft 13. Is cut off.

  As shown in FIGS. 9 and 10, the swing link 42 of each one-way clutch 36 includes a cylindrical portion 42b having an inner peripheral surface 42a formed therein, and a first extending radially outward from one axial end side of the cylindrical portion 42b. The first flange portion 42c and the second flange portion 42d extending radially outward from the other axial end of the cylindrical portion 42b are provided, and the first and second flange portions 42c and 42d protrude most radially outward. A small end portion of the connecting rod 33 is pivotally supported by a pin 37 at the portion. The thickness in the radial direction of the first and second flange portions 42c and 42d is different, and the thickness t1 in the radial direction of the first flange portion 42c located on the restraining end side (right end side in FIG. 1) of the output shaft 13 is different. Is set smaller than the radial thickness t2 of the second flange portion 42d located on the free end side (left end side in FIG. 1) of the output shaft 13. As a result, the swing link 42 has low radial rigidity on the restraining end side and high radial rigidity on the free end side.

  The swing link 42 of the present embodiment is manufactured by forging, and the mating surface P (see FIG. 10) of the forging die is set to a portion where the radial thickness t2 of the second flange 42d is the largest. The As a result, the swing link 42 can be easily removed and the productivity is improved.

  As already described with reference to FIG. 12, the output shaft 13 outputs a driving force to the differential gear D from the spline 13b (see FIG. 1) formed at the right end (restraint end). The left end (free end) of the output shaft 13 is twisted relative to the right end (restraint end) due to torque input from the plurality of one-way clutches 36 supported on the outer periphery of each of the one-way clutches 36. The relative rotation angle between the inner peripheral surface 42a of the swing link 42 and the outer peripheral surface 13a of the output shaft 13 becomes smaller by the twist of the output shaft 13 at the left end portion of the roller 41 of the clutch 36 than at the right end portion. Compared with the right end portion, the left end portion has a shallower engagement between the inner peripheral surface 42a of the swing link 42 and the outer peripheral surface 13a of the output shaft 13 and the surface pressure is reduced. The inclination of the roller 41 may occur turned Ichika.

  However, according to the present embodiment, the rigidity of the second flange 42d of the swing link 42 facing the left end of the roller 41 where the surface pressure greatly decreases is increased by increasing the radial thickness t2. In addition, since the rigidity of the first flange portion 42c of the swing link 42 facing the right end side of the roller 41 where the surface pressure does not decrease so much is decreased by reducing the radial thickness t1, the surface pressure is reduced in the axial direction. It is possible to prevent the roller 41 from tilting and to enable the one-way clutch 36 to be smoothly engaged.

Second and third embodiments

  Next, second and third embodiments of the present invention will be described with reference to FIG.

  In the swing link 42 of the second embodiment shown in FIG. 11 (A), the radial thickness of the cylindrical portion 42b is set to be small at t1 on the restraint end side and lowered in rigidity, and is set to be large at t2 on the free end side. High rigidity. In addition, the swing link 42 of the third embodiment shown in FIG. 11B has a low rigidity by setting the axial thickness of the first flange portion 42c on the restraint end side to be small t1, and the first end on the free end side. The rigidity of the two flange portions 42d is increased by setting the thickness in the axial direction to be large t2. Also according to the second and third embodiments, the same operational effects as those of the first embodiment described above can be achieved.

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.

  For example, although the output shaft 13 is provided at the shaft end of the spline 13b that is a driving force output portion in the embodiment, it may be provided at the intermediate portion in the axial direction of the output shaft 13.

  The drive source of the present invention is not limited to the engine E of the embodiment, and may be another type of drive source such as a motor / generator.

12 Input shaft 13 Output shaft 13a Outer peripheral surface 13b Spline (driving force output section)
14 Transmission unit 19 Eccentric disc (Eccentric member)
33 Connecting rod 36 One-way clutch 41 Roller 42 Swing link 42a Inner peripheral surface E Engine (drive source)

Claims (2)

A transmission unit (14) for shifting the rotation of the input shaft (12) connected to the drive source (E) and transmitting it to the output shaft (13);
The transmission unit (14)
An eccentric member (19) rotating eccentrically integrally with the input shaft (12);
A swing link (42) supported swingably on the output shaft (13);
Arranged between the output shaft (13) and the swing link (42) and engaged when the swing link (42) swings in one direction and disengaged when swings in the other direction. The one-way clutch (36)
A vehicle power transmission device comprising a connecting rod (33) connecting the eccentric member (19) and the swing link (42),
The one-way clutch (36) includes a plurality of rollers (41) disposed between an inner peripheral surface (42a) of the swing link (42) and an outer peripheral surface (13a) of the output shaft (13), The output shaft (13) includes a driving force output portion (13b) that outputs a driving force to the driving wheel, and the swing link (42) is configured to drive the drive between one end side and the other end side sandwiching the axial center. A vehicle power transmission characterized in that the side near the force output portion (13b) is thin in the radial direction or axial direction and the side far from the driving force output portion (13b) is thick in the radial direction or axial direction. apparatus.   Of the one end side and the other end side sandwiching the center in the axial direction, the swing link (42) is thin in the radial direction on the side close to the drive force output section (13b), and the drive force output section (13b) The vehicular power transmission device according to claim 1, wherein the side far from the center is thick in the radial direction.

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